2.5 The board of directors of a city-owned electric power plant in a large urban city wants to assess the increase in electricity demands due to sources such as hybrid cars, big-screen TVs, and other entertainment devices in the home. There are a number of different sampling plans that can be implemented to survey the residents of the city. What are the relative merits of the follow- ing sampling units: individual families, dwelling units (single-family homes, apartment buildings, etc.), and city blocks? 2.6 A large auto parts supplier with distribution centers throughout the United States wants to survey its employees concerning health insurance coverage. Employee insurance plans vary greatly from state to state. The company wants to obtain an estimate of the annual health insur- ance deductible its employees would find acceptable. What sampling plan would you suggest to the company to achieve its goal? 2.7 The circuit judges in a rural county are considering a change in how jury pools are selected for felony trials. They ask the administrator of the courts to assess the county residents' reaction to changing the requirement for membership in the jury pool from the current requirement of all registered voters to a new requirement of all registered voters plus all residents with a current driver's license. The administrator sends questionnaires to a random sample of 1,000 people from the list of registered voters in the county and receives responses from 253 people. a. What is the population of interest? b. What is the sampling frame? c. What possible biases could be present in using the information from the survey?